Electrical relay



1932- J. w. LIVINGSTON 1,344,169

ELECTRICAL RELAY Filed Feb. 2, 1931 INVENTOR. J 14 L1 xflnqston,

Q a, M ATTORNEY.

Patented Feb. 9, 1932 UNITED STATES PATENT OFFICE JOHN W. LIVINGSTON, 01 WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE PIION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION 01 PENNSYLVANIA ELECTRICAL RELAY My invention relates to electrical relays,

and particularly to electrical relays of the type comprising a winding and a contact which is operated if and only if the w1n.d1ng

isenergized a plurality of times in such man-" nor that the length of the time interval which elapses between successive energ1zations is less than a redetermined value.

' I will describe one form of relay embodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a v1ew,partly in elevation, and partly diagrammatic,

showing one form of relay embodying my invention.

cillate about a .horizontal axis, indicated at 4 in the drawing. When electromagnet 1 is deenergized, the arm 3 is held against an adjustable stop screw 5 by means of a spring .6, but when electromag'net 1 becomes energized, this arm is rotated in a counterclockwise direction, to a position in which the armature 2 engages a core pin 7 attached to the core of electromagnet 1.

Pivoted to the arm 2 is'a propelling pawl 8 which is adapted to engage one of the teeth of a ratchet wheel 9 each time magnet '1 becomes energized. The. pawl 8 is guided into engagement with the teeth of the wheel 9 in the desired manner by means of a fixed pin 10 against which the underside of the pawl rests. The ratchet wheel 9 is fixed to a rotatable shaft 11, and is biased to the position shown by means of a counter-weight 12 formed integral with a cam 13 which is also fixed to the shaft .11. It will be noted 7 that the'ratchet wheel is provided with teeth on only a portion of its circumference, the reasonfor this being explained more fully hereinafter.

Also pivoted to the arm 3 at the lower end of the arm is a link 14, the free end of which is\ provided with an elongated slot 15. A horizontal pin 16 attached to the side andcontrols a detent 21 which is adapted to at times engage the teeth of the ratchet wheel, as will be explained hereinafter.

The detent 21 is also mounted to oscillate about the axis 20, and is normally heldagainst an offset portion 22 formed on the upper end of the pendulum '17, by means of a suitable spring 22 which is secured to the pendulum. The bob 24 of the pendulum is adjustably secured to the pendulum in such manner that it may be raised or lowered, so that the period of the pendulum can be regulated within certain limits.

The cam 13 is provided with a cam swell 25 which cooperates with a camfollower 26 attached to a contact finger 27. When the parts are in their normal positions, in which they are illustrated in the drawing, the cam follower 26 is out of engagement with the cam swell 25, and the contact finger 27 then engages a fixed contact 27 to close a contact 27 27". If, however, the ratchet wheel is rotated through a suflicient angle in a clockwise direction, the cam follower 26 rides up on top of the cam swell 25, and the finger 27 then engages a fixed contact 27 to close a contact 27--27 The operation of the relay as a whole is as follows: When electromagnet 1 becomes energized, arm 3 is rotated to the position in which armature 2 engages core pin 7 as previously described. This rotation of the arm causes pawl 8 to rotate the ratchet wheel 9 one tooth in a clockwise direction, and also causes pendulum 17 to swing in a counterclockwise direction about axis 20, to-a position in which detent 21 engages an adjacent tooth of the ratchet wheel 9, the detentsubsequently being held in engagement with the tooth by means of the spring 23. When endulum 17 so'that the pendulum is now ee to swing back to its normal position under the influence of gravity. The detent 21 is so arranged that it will remain in engagement with the ratchet wheel until the pendulum hasreturned substantially to its normal position, at which time the ofi'set portion 22 engages the pawl and automatically withdraws it from engagement with the ratchet wheel. It will be apparent, therefore, that if ratchet wheel 9 has been advanced due to the energization of electromagnet 1, this wheel will subsequently remain in its advanced position until electromagnet 1 has again become deenergized, and an interval "of time has elapsed thereafter which is long enough for pendulum 17 to swing back to its normal position. As soon as the pendulum has returned to its normal position, the subsequent withdrawal of detent 21 just described releases the ratchet wheel 9, and counter-weight 12 then rotates the ratchet wheel in a clockwise direction to bring the ratchet wheel back to its original position.

It follows from the foregoing that if electromagnet 1 is energized a plurality of times in such manner that the time interval which elapses between successive energizations is less than the time interval required for pendulum 17 to return to its normal position after each lmpulse, the ratchet wheel 9 will be rotated with a step by step movement until the pawl 8 engages the "last tooth, after which ated position until electromagnet 1 becomes deenergized for a time interval which is long enough for pendulum 17 to swing back to its is not essential to my invention, however, and

may be varied as conditions require by varying the relative position of the cam and ratch-.

et wheel and by increasing or decreasing the number of teeth on the ratchet wheel t correspond. It will be apparent from the foregoing that I have provided a relay which will operate its contacts when and only when the electromagnet 1 is energiz'edin such manner that the further rotation of the wheel is prevented.

time which elapses between successive energizations is less than a time interval which made therein within the scope of the up pended claims without departing from the spirit and scope of my invention.

Having thus described myinvention, what I claim is:

1. In combination, a member biased to one position, means for moving said member from said one position in a step by step movement, a pendulum, means for imparting movement to said pendulum each time sald member is stepped, and means for preventing said member from returning to said one position between successive movements unless the time interval whichelapses between successive movements exceeds a time interval which depends upon the period of said pendulum.

2. In combination, a member biased to one position, means for moving said member from said one position in astep by step movement, a pendulum, means controlled by said pendulum and effective when said pendulum is swung from its normal position in one direction for holding said wheel in its stepped po-' sition until said pendulum has returned to its normal position, and means for swinging said pendulum in said one direction each time said member is stepped.

3. In combination, a member biased to one position, means for moving said member from said one position in a step by step movement, a pendulum, means for swinging said pendulum from its normal position each time said member is moved, and means controlled by said pendulum and effective for preventing said ember from returning to said one position between successive movements if and only if thetime which elapses between suc cessive movements is less than the time required for said pendulum to return to its normal position.

- 4. In combination, a toothed member biased t'oone position and adapted to he stepped in opposition to said bias, ,means for stepping said member, a pendulum, a detent controlled by said pendulum in such manner that if said pendulum is swung from its normal position in one direction said detent will engage one of the teeth of said member and subsequent ly remain in engagement with such tooth until said pendulum has returned to its normal-position, and means for swinging said pendulum from its normal position in one direction each time said member is stepped.

5. In combination, a toothed member biased to one position and adapted to be stepped in opposition to said bias, means for stepping said member, a pendulum, a detent controlled by said pendulum in such manner that ifsaid pendulum is swung from its IIOIIIlll'POSltlOIl in one direction said detent will at times engage one of the teeth of said member and subsequently remain in engagementlwith such tooth until said pendulum has returned to its normal position, means for swinging said pendulum from its normal position in one direction each time said member is stepped, a contact, and means controlled by said member for operating said contact when said member has been stepped to a predetermined position.

6. In combination, a toothedmember biased to one position and adapted to be stepped in opposition to said bias, means including an electromagnet for stepping said member,

a pendulum, a detent controlled by said pendulum in such manner that if said pendulum cumference and biased to one position, a pro-' teeth of said .wheel and remain in engagement with such tooth thereafter until said pendulum has returned to its normal position, means attached to said arm for swinging said pendulum from its normal position in said one direction each time said arm is 0scillated, a contact, and means controlled by said toothed wheel for operatin said contact when said toothed wheel has een moved from said one position through a predetermined angular distance.

In testimony whereof I aflix my signature.

' @JOHN W. LIVINGSTON.

is swung from its normal position in one direction said detent will enga e one of the teeth of said members and su sequently remain in engagement with such tooth until said pendulum has returned to its normal position, and means for swinging said pendulum from its normal position in one direction each time said member is stepped.

7 In combination, a first member adapted to be oscillated, means for oscillating said first member, a toothed member biased to one 7 position, a propelling pawl actuated by said first member and arranged to move said toothed member one tooth each time said first member is oscillated, a detent adapted when moved-into engagement with said toothed member to retain said toothed member in its stepped position fora predetermined time interval, and means 'for moving said detent into engagement with said am thed member each time said first member is oscillated.

8. In combination, a. first member adapted to be oscillated, means for oscillating said first member, a toothed member biased to one position, a propelling pawl actuated by said with said toothed member, and means actuated by said first member for moving said detent into engagement with said first member each time said first member is stepped and for subsequently maintainingsaid detent in engagement with said toothed member until a predetermined time interval has elapsed.

9. In combination, a pivoted arm biased to one position, an armature attached to'said arm, an electromagnet cooperating with said armature for oscillating said arm, a wheel provided with teeth on a portion of its cir- 

